In a large mixing bowl, cream together the sugar and butter.
Then mix in the flour, baking powder, salt, egg, and milk, mixing well.
Pour the batter into greased muffin tins (or greased silicone muffin cups), filling each cavity about 2/3 way full.
Set into the air fryer for 12-15 minutes at 320 degrees F (air fryer setting)
In one bowl, mix the cinnamon and sugar, and in another bowl, melt some butter.
Once the muffins are done, dip the muffin into the melted butter and then into the cinnamon and sugar mixture.
Sprinkle some sparkling sugar on top.
Plate, serve, and enjoy!